Insulin binding to circulating monocytes has been evaluated in different conditions of insulin resistance (acromegaly, ataxia-telangiectasia, hypercorticolism) as well as in patients with insulinoma and even in normal subjects. Insulin receptor concentration is inversely correlated with the concentration of plasma insulin. The affinity of receptor can be reduced by the presence of anti-receptor antibodies, or can be increased in acromegaly or changed by ingestion for glucose in normal subjects. BIBLIOGRAPHIC REFERENCE: Bar, R.S., Gorden, P., Roth, J., and Siebert, C.W.: Insulin receptors in patients with insulinomas: Changes in receptor affinity and concentration. J. Clin. Endocrinol. Metab. 44: 1210-1213, 1977.